From f4ec7cb0f9ea65a7622b001bb48dbac1a7e6ad1e Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Sat, 6 Oct 2018 19:35:06 +0200 Subject: [PATCH] mac80211: minstrel: do not sample rates 3 times slower than max_prob_rate These rates are highly unlikely to be used quickly, even if the link deteriorates rapidly. This improves throughput in cases where CCK rates are not reliable enough to be skipped entirely during sampling. Sampling these rates regularly can cost a lot of airtime. Signed-off-by: Felix Fietkau Signed-off-by: Johannes Berg --- net/mac80211/rc80211_minstrel_ht.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c index fdcb4e9b4560..f466ec37d161 100644 --- a/net/mac80211/rc80211_minstrel_ht.c +++ b/net/mac80211/rc80211_minstrel_ht.c @@ -1004,10 +1004,13 @@ minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) return -1; /* - * Do not sample if the probability is already higher than 95% - * to avoid wasting airtime. + * Do not sample if the probability is already higher than 95%, + * or if the rate is 3 times slower than the current max probability + * rate, to avoid wasting airtime. */ - if (mrs->prob_ewma > MINSTREL_FRAC(95, 100)) + sample_dur = minstrel_get_duration(sample_idx); + if (mrs->prob_ewma > MINSTREL_FRAC(95, 100) || + minstrel_get_duration(mi->max_prob_rate) * 3 < sample_dur) return -1; /* @@ -1017,7 +1020,6 @@ minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) cur_max_tp_streams = minstrel_mcs_groups[tp_rate1 / MCS_GROUP_RATES].streams; - sample_dur = minstrel_get_duration(sample_idx); if (sample_dur >= minstrel_get_duration(tp_rate2) && (cur_max_tp_streams - 1 < minstrel_mcs_groups[sample_group].streams ||